package com.pig4cloud.pigx.admin.util;

import com.baomidou.mybatisplus.core.toolkit.CollectionUtils;
import com.pig4cloud.pigx.admin.entity.ExcelColumn;
import org.apache.commons.lang3.BooleanUtils;
import org.apache.commons.lang3.CharUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.math.NumberUtils;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.MediaType;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.math.BigDecimal;
import java.net.URLEncoder;
import java.util.*;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.stream.Collectors;
import java.util.stream.Stream;

/**
 * @author gaoxiao
 * @description
 * @date 2020/3/27 15:27
 **/
public class ExcelUtils {

	private final static Logger log = LoggerFactory.getLogger(ExcelUtils.class);

	private final static String EXCEL2003 = "xls";
	private final static String EXCEL2007 = "xlsx";

	public static <T> List<T> readExcel(String path, Class<T> cls,MultipartFile file){

		String fileName = file.getOriginalFilename();
		if (!fileName.matches("^.+\\.(?i)(xls)$") && !fileName.matches("^.+\\.(?i)(xlsx)$")) {
			log.error("上传文件格式不正确");
		}
		List<T> dataList = new ArrayList<>();
		Workbook workbook = null;
		try {
			InputStream is = file.getInputStream();
			if (fileName.endsWith(EXCEL2007)) {
//                FileInputStream is = new FileInputStream(new File(path));
				workbook = new XSSFWorkbook(is);
			}
			if (fileName.endsWith(EXCEL2003)) {
//                FileInputStream is = new FileInputStream(new File(path));
				workbook = new HSSFWorkbook(is);
			}
			if (workbook != null) {
				//类映射  注解 value-->bean columns
				Map<String, List<Field>> classMap = new HashMap<>();
				List<Field> fields = Stream.of(cls.getDeclaredFields()).collect(Collectors.toList());
				fields.forEach(
						field -> {
							ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
							if (annotation != null) {
								String value = annotation.value();
								if (StringUtils.isBlank(value)) {
									return;//return起到的作用和continue是相同的 语法
								}
								if (!classMap.containsKey(value)) {
									classMap.put(value, new ArrayList<>());
								}
								field.setAccessible(true);
								classMap.get(value).add(field);
							}
						}
				);
				//索引-->columns
				Map<Integer, List<Field>> reflectionMap = new HashMap<>(16);
				//默认读取第一个sheet
				Sheet sheet = workbook.getSheetAt(0);

				boolean firstRow = true;
				for (int i = sheet.getFirstRowNum(); i <= sheet.getLastRowNum(); i++) {
					Row row = sheet.getRow(i);
					//首行  提取注解
					if (firstRow) {
						for (int j = row.getFirstCellNum(); j <= row.getLastCellNum(); j++) {
							Cell cell = row.getCell(j);
							String cellValue = getCellValue(cell);
							if (classMap.containsKey(cellValue)) {
								reflectionMap.put(j, classMap.get(cellValue));
							}
						}
						firstRow = false;
					} else {
						//忽略空白行
						if (row == null) {
							continue;
						}
						try {
							T t = cls.newInstance();
							//判断是否为空白行
							boolean allBlank = true;
							for (int j = row.getFirstCellNum(); j <= row.getLastCellNum(); j++) {
								if (reflectionMap.containsKey(j)) {
									Cell cell = row.getCell(j);
									String cellValue = getCellValue(cell);
									if (StringUtils.isNotBlank(cellValue)) {
										allBlank = false;
									}
									List<Field> fieldList = reflectionMap.get(j);
									fieldList.forEach(
											x -> {
												try {
													handleField(t, cellValue, x);
												} catch (Exception e) {
													log.error(String.format("reflect field:%s value:%s exception!", x.getName(), cellValue), e);
												}
											}
									);
								}
							}
							if (!allBlank) {
								dataList.add(t);
							} else {
								log.warn(String.format("row:%s is blank ignore!", i));
							}
						} catch (Exception e) {
							log.error(String.format("parse row:%s exception!", i), e);
						}
					}
				}
			}
		} catch (Exception e) {
			log.error(String.format("parse excel exception!"), e);
		} finally {
			if (workbook != null) {
				try {
					workbook.close();
				} catch (Exception e) {
					log.error(String.format("parse excel exception!"), e);
				}
			}
		}
		return dataList;
	}

	private static <T> void handleField(T t, String value, Field field) throws Exception {
		Class<?> type = field.getType();
		if (type == null || type == void.class || StringUtils.isBlank(value)) {
			return;
		}
		if (type == Object.class) {
			field.set(t, value);
			//数字类型
		} else if (type.getSuperclass() == null || type.getSuperclass() == Number.class) {
			if (type == int.class || type == Integer.class) {
				field.set(t, NumberUtils.toInt(value));
			} else if (type == long.class || type == Long.class) {
				field.set(t, NumberUtils.toLong(value));
			} else if (type == byte.class || type == Byte.class) {
				field.set(t, NumberUtils.toByte(value));
			} else if (type == short.class || type == Short.class) {
				field.set(t, NumberUtils.toShort(value));
			} else if (type == double.class || type == Double.class) {
				field.set(t, NumberUtils.toDouble(value));
			} else if (type == float.class || type == Float.class) {
				field.set(t, NumberUtils.toFloat(value));
			} else if (type == char.class || type == Character.class) {
				field.set(t, CharUtils.toChar(value));
			} else if (type == boolean.class) {
				field.set(t, BooleanUtils.toBoolean(value));
			} else if (type == BigDecimal.class) {
				field.set(t, new BigDecimal(value));
			}
		} else if (type == Boolean.class) {
			field.set(t, BooleanUtils.toBoolean(value));
		} else if (type == Date.class) {
			//
			field.set(t, value);
		} else if (type == String.class) {
			field.set(t, value);
		} else {
			Constructor<?> constructor = type.getConstructor(String.class);
			field.set(t, constructor.newInstance(value));
		}
	}

	private static String getCellValue(Cell cell) {
		if (cell == null) {
			return "";
		}
		if (cell.getCellType() == Cell.CELL_TYPE_NUMERIC) {
			if (DateUtil.isCellDateFormatted(cell)) {
				return HSSFDateUtil.getJavaDate(cell.getNumericCellValue()).toString();
			} else {
				return new BigDecimal(cell.getNumericCellValue()).toString();
			}
		} else if (cell.getCellType() == Cell.CELL_TYPE_STRING) {
			return StringUtils.trimToEmpty(cell.getStringCellValue());
		} else if (cell.getCellType() == Cell.CELL_TYPE_FORMULA) {
			return StringUtils.trimToEmpty(cell.getCellFormula());
		} else if (cell.getCellType() == Cell.CELL_TYPE_BLANK) {
			return "";
		} else if (cell.getCellType() == Cell.CELL_TYPE_BOOLEAN) {
			return String.valueOf(cell.getBooleanCellValue());
		} else if (cell.getCellType() == Cell.CELL_TYPE_ERROR) {
			return "ERROR";
		} else {
			return cell.toString().trim();
		}

	}

	public static <T> void writeExcel(HttpServletResponse response, List<T> dataList, Class<T> cls){
		Field[] fields = cls.getDeclaredFields();
		List<Field> fieldList = Arrays.stream(fields)
				.filter(field -> {
					ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
					if (annotation != null && annotation.col() > 0) {
						field.setAccessible(true);
						return true;
					}
					return false;
				}).sorted(Comparator.comparing(field -> {
					int col = 0;
					ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
					if (annotation != null) {
						col = annotation.col();
					}
					return col;
				})).collect(Collectors.toList());

		Workbook wb = new XSSFWorkbook();
		Sheet sheet = wb.createSheet("Sheet1");
		AtomicInteger ai = new AtomicInteger();
		{
			Row row = sheet.createRow(ai.getAndIncrement());
			AtomicInteger aj = new AtomicInteger();
			//写入头部
			fieldList.forEach(field -> {
				ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
				String columnName = "";
				if (annotation != null) {
					columnName = annotation.value();
				}
				Cell cell = row.createCell(aj.getAndIncrement());

				CellStyle cellStyle = wb.createCellStyle();
				cellStyle.setFillForegroundColor(IndexedColors.WHITE.getIndex());
				cellStyle.setFillPattern(CellStyle.SOLID_FOREGROUND);
				cellStyle.setAlignment(CellStyle.ALIGN_CENTER);

				Font font = wb.createFont();
				font.setBoldweight(Font.BOLDWEIGHT_NORMAL);
				cellStyle.setFont(font);
				cell.setCellStyle(cellStyle);
				cell.setCellValue(columnName);
			});
		}
		if (CollectionUtils.isNotEmpty(dataList)) {
			dataList.forEach(t -> {
				Row row1 = sheet.createRow(ai.getAndIncrement());
				AtomicInteger aj = new AtomicInteger();
				fieldList.forEach(field -> {
					Class<?> type = field.getType();
					Object value = "";
					try {
						value = field.get(t);
					} catch (Exception e) {
						e.printStackTrace();
					}
					Cell cell = row1.createCell(aj.getAndIncrement());
					if (value != null) {
						if (type == Date.class) {
							cell.setCellValue(value.toString());
						} else {
							cell.setCellValue(value.toString());
						}
						cell.setCellValue(value.toString());
					}
				});
			});
		}
		//冻结窗格
		wb.getSheet("Sheet1").createFreezePane(0, 1, 0, 1);
		//浏览器下载excel
		buildExcelDocument("abbot.xlsx",wb,response);
		//生成excel文件
//        buildExcelFile(".\\default.xlsx",wb);
	}

	/**
	 * 浏览器下载excel
	 * @param fileName
	 * @param wb
	 * @param response
	 */

	private static  void  buildExcelDocument(String fileName, Workbook wb,HttpServletResponse response){
		try {
			response.setContentType(MediaType.APPLICATION_OCTET_STREAM_VALUE);
			response.setHeader("Content-Disposition", "attachment;filename="+URLEncoder.encode(fileName, "utf-8"));
			response.flushBuffer();
			wb.write(response.getOutputStream());
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	/**
	 * 生成excel文件
	 * @param path 生成excel路径
	 * @param wb
	 */
	private static  void  buildExcelFile(String path, Workbook wb){

		File file = new File(path);
		if (file.exists()) {
			file.delete();
		}
		try {
			wb.write(new FileOutputStream(file));
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}